System.Diagnostics.Process.WaitForExitCore C# (CSharp) Method

        private bool WaitForExitCore(int milliseconds)
        {
            SafeProcessHandle handle = null;
            bool exited;
            ProcessWaitHandle processWaitHandle = null;
            try
            {
                handle = GetProcessHandle(Interop.Advapi32.ProcessOptions.SYNCHRONIZE, false);
                if (handle.IsInvalid)
                {
                    exited = true;
                }
                else
                {
                    processWaitHandle = new ProcessWaitHandle(handle);
                    if (processWaitHandle.WaitOne(milliseconds))
                    {
                        exited = true;
                        _signaled = true;
                    }
                    else
                    {
                        exited = false;
                        _signaled = false;
                    }
                }
            }
            finally
            {
                if (processWaitHandle != null)
                {
                    processWaitHandle.Dispose();
                }

                // If we have a hard timeout, we cannot wait for the streams
                if (_output != null && milliseconds == Timeout.Infinite)
                {
                    _output.WaitUtilEOF();
                }

                if (_error != null && milliseconds == Timeout.Infinite)
                {
                    _error.WaitUtilEOF();
                }

                ReleaseProcessHandle(handle);
            }

            return exited;
        }